SU1691697A1 - Method of simulation of two-layer multiple density flows and device - Google Patents

Abstract

The invention relates to the hydraulics of multi-density flows and can be used in the hydraulic modeling of structures operating under conditions of water bodies having a two-layer multi-density stratification. The purpose of the invention is an input 8-to-1 distribution device improving the accuracy of modeling by maintaining the interface between salt and fresh water in the tray in the desired altitude position. The device contains tray 1. A pool 2 with a partition 3 mounted inclined towards the tray 1 with the possibility of changing the height position of the upper edge 4. There is a salt water pipeline 5, a fresh water pipeline 6 and a discharge pipe 7. Pipelines 5 and 6 continuously supply , respectively, salt and fresh water. Fresh water is supplied to the inlet of tray 1. Solen water fills the space under the partition 3 and spreads to tray 1, simulating the inlet of salt water at the mouth of a river or other hydraulic object. Salt water overflows into chamber 8 through edge 4, and then saline water along with fresh water enters discharge pipe 7. Fresh water supplied through pipeline 6 spreads in the upper layer of chamber 8 of basin 2 and tray 1. As a result, a stable boundary between salted and fresh water. 2 з.п /. Ф-л, 1 Il. About h with VI y

Description

The invention relates to the hydraulics of heterogeneous streams and can be used in hydraulic modeling of structures operating in reservoirs with two-layer heterogeneous stratification, for example, in studying the operation of hydraulic structures in the estuaries of rivers and estuaries, some types of discharge facilities, through which the discharge sewage or industrial wastes into natural reservoirs or sludge accumulators having a two-layer heterogeneous stratification.

The purpose of the invention is to improve the accuracy of modeling by maintaining the boundary between saline and fresh water in the tray at the desired altitude position.

The drawing shows the device, a vertical section.

The device contains a hydraulic, tray 1, in which studies are carried out, pool 2, adjacent to tray 1 and used to create the required boundary conditions. Pool 2 is equipped with an separating partition 3, installed at the bottom of the pool at an angle to it with an inclination toward the tray 1 and with the possibility of setting the upper edge 4 in height depending on the position of the flow interfaces required by the research conditions. The inlet of the saline water pipeline 5 is located under the partition 3, and the inlet of the fresh water pipeline 6 is above the partition 3. The waste pipeline 7, intended to drain out the intermediate salinity water resulting from the interaction of fresh and salt water, beyond the basin 2 2. Position 8 marked drain chamber.

Supply pipes 5 and 6 to pool 2 and chamber 8 are supplied with salt and fresh water, respectively, at a constant flow rate. In this case, the upper edge 4 of the partition wall 3 is set below the required level of the interface between the flows by the value of h

h - G P1. (Qc 2

 () 3

where h is the thickness of the salt water layer above the partition, m;

g — acceleration of the force of gravity, m / s;

pi is the density of fresh water, kg / m;

Ap p2 -p1,

/ 02 - density of salt water, kg / m;

Qc - salt water consumption, m3 / s;

K - coefficient of proportionality;

B - the width of the drain chart of the dividing partition, m

Fresh water is supplied to the inlet of tray 1. Salt water flowing through conduit 5 fills the space under partition wall 3 and spreads into tray 1. When the top edge 4 of partition 3 is exceeded, saline water overflows through edge 4, and the saline water, having a greater density, flows to the place where the discharge pipe 7 starts. The water with intermediate concentration also flows there. Salt water overflows through the upper edge 4 in a layer of thickness h, which is taken into account when assigning the mark of the upper edge 4 of the dividing wall 3. Fresh water is fed into the basin through pipeline 6, it spreads in the upper layer of chamber 8, basin 2 and tray 1. Ta the part which, interacting with salt water, has acquired some intermediate concentration, is removed beyond

basin by discharge pipe 7. To change the position of the flow interface, it is sufficient to change the top level of the partition wall 3 and to stand for some time to bring the system into

New set mode.

Claims (2)

Claim 1. Method for modeling two-layer multi-density flows, including flow into the inlet part of the hydraulic tray of fresh water, flow into the lower part of the basin, adjacent to the outlet of the tray, salt water, collection of mixed water flowing over a transverse partition installed in the pool in the drain The chamber and the discharge of water from the drain chamber, characterized in that, in order to increase the modeling accuracy by maintaining the boundary between saline and fresh water in the tray at the desired altitude, fresh water is supplied to the upper part of the drain chamber, and the upper edge of the partition is set below the required salt / fresh water interface by where h is the thickness of the salt water layer above the partition, m; p is the density of fresh water, kg / m3; Dr p2 -pi, pi is the density of salt water, kg / m3; Qc - salt water consumption, m3 / s; K - coefficient of proportionality; B - the width of the discharge part of the dividing partition, m 2. A device for simulating double-layered multi-density flows, including a hydraulic tray, adjacent to the outlet part of the tray, a pool with a transverse overflow partition, forming a drain chamber in the end of the pool, supplying a salt water pipeline connected to the bottom of the pool before the partition, and a waste pipeline 0 connected to the lower part of the chamber, which is characterized by the fact that, in order to increase the modeling accuracy by maintaining the boundary between saline and fresh water in the tray at the desired altitude, it is supplied with a fresh water inlet pipe connected to the upper part of the drain chamber; the partition is made with the possibility of changing the height position of the upper water edge and is installed with an inclination towards the tray.